Aculight proposes developing novel non-linear optical configurations to access any wavelength in the near and deep UV. We set a long term goal of 20 to 50 Watts of cw or ultra-high pulse rate mode locked UV output. The UV output will initially be at pre-set wavelength, and will be tunable with further development. Conversion efficiency from green to wavelength diverse UV outputs of up to 50% appear possible. The novel non-linear optical converter features an OPO in tandem with a mixing crystal. In comparison to other ring type converter geometries, the proposed configuration appears to have significant practical advantages in the area of optical/mechanical stability and control. Phase I examines analytically and experimentally the power conversion limitations of a fixed frequency UV output ring non-linear optical converter. Though ultimately driven by a diode pumped solid state laser, initial experiments will use conventional Nd drive lasers. In Phase I, a streat of cw-mode locked pulses drives the converter. To evaluate pure cw pumping and output, experiments and analysis will examine lowering the cavity losses and ring threshold. Phase I defines the design of development experiments as well as a more capable converter packate built in Phase II. The effort will have a strong synergy with other Aculight efforts, and compliments activities at the Air Force Phillips Laboratory in exploring analogous techniques for other wavelengths.